Studies of melanoma risk and use of female sex steroids and menstrual and reproductive events in women have yielded inconsistent results and have had insufficient sample size to address many important questions. To provide a more complete and precise assessment of these factors, we propose to pool data from 11 of the largest melanoma case-control studies completed to date. The data to be analyzed were collected through personal interviews with over 6,000 women (>2,500 cases and >3,500 controls). Specific hypotheses of interest include: 1) the potential risk of melanoma associated with long term oral contraceptive use, 10 or more years after first use, and 2) the effect of reproductive history, non- contraceptive hormones and surgical menopause on melanoma risk. We will use a uniform variable definition and coding scheme and apply a common analysis approach to each study individually. Next, a joint analysis will be performed using an innovative two-step approach. The investigative team will meet to review the results and to discuss their interpretation. Our approach will enable us to answer crucial questions regarding the role of female sex hormones on melanoma risk in a substantially more efficient and timely manner than undertaking a new study of this size.